Butch Kronlund, president of the Coastlands Mutual Water Co., walks in an area in Big Sur where seven of 137 bay laurel trees in a recent survey tested positive for the microbe that causes sudden oak death.

Butch Kronlund, president of the Coastlands Mutual Water Co., walks...

The California drought is helping save the state's signature tree - the mighty oak - by slowing down the spread of the plague-like disease scientists call sudden oak death.

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